1. Field of the Invention
The present invention generally relates to a dual link internal combustion engine. More specifically, the present invention relates to a dual link internal combustion engine in which a piston and a crankshaft are coupled via a dual link piston-crank mechanism.
2. Background Information
Various dual link internal combustion engines have been proposed in which a crank pin of a crankshaft and a piston pin of a piston are coupled by a plurality of links. One example of such an engines is disclosed in Japanese Patent Publication No. 3911977. In this publication, a dual link piston-crank mechanism is disclosed in which the center position of a piston pin is offset to one side from a piston center axis, the piston's center of gravity position is offset to the other side relative to a piston reciprocation line passing through the piston pin center and extending in a cylinder axial direction, and the orientation of the piston is controlled when the piston bears thrust force. Specifically, by considering factors such as the position of the point where a combustion load or an inertial load acts on the piston, and the direction of the tilt of the link, the highly rigid top end of the piston can be suppressed from colliding with the side surface of the cylinder, and friction loss and noise can be reduced.